[Changes in the unit activity of bulbar respiratory neurons during acute hypoxia].

The changes of respiratory neurons (RS) activity had a phasic character in acute hypoxia. At the initial stage of the hypoxia (the altitude 4000-5000 m), the firing rate of inspiratory (IN) and expiratory (EN) neurons was increasing whereas at the maximum altitude (8000-9000 m) it was decreasing. After the descent, the background RN activity restored. The comparative analysis of RN resistance to hypoxia showed higher resistance of IN than of EN which determined the entire reaction of the respiratory system, viz. the more stable phase of inspiration. A great number of IN were revealed at the altitude of 8000-9000 m which had been in the state of inhibition for a long time under conditions of normoxia but became activated with the acute oxygen deficiency.